1. Field of the Invention
The present invention relates to a correcting method for correcting a misregistration which is used in an image processing apparatus.
2. Description of the Related Art
There are mainly two kinds of methods of misregistration correction (hereinbelow, called “trapping”) for correcting a deviation of a printing position of each of colors of C, M, Y, and K in a color printer. One is a method of executing a trapping process to data of a vector format such as intermediate data formed from printer description language data (hereinbelow, called “PDL data”) or PDF data. Data of a format such as PS (PostScript), PDF (Portable Document Format), or the like is included in the printer description language data.
The other is a method of executing the trapping process to a bit map (raster format) in which a rendering of the PDL data has been completed (Japanese Patent No. 02639518).
According to the trapping process of the vector format, a drawing object is increased on the basis of information of a neighboring/overlap relation of each drawing object or an addition (trapping object) or the like of a drawing object is performed. Therefore, various kinds of methods can be utilized when the trapping object for a width or a white gap is embedded and the advanced trapping process can be realized. However, an edge management of every drawing object, a management of the trapping object, and the like are necessary.
According to the trapping process of the raster format, a neighboring portion is calculated on the basis of colors of a target pixel and an adjacent pixel in a bit map and a pixel correction is made. However, a pixel correcting method is limited and various techniques are necessary to raise calculating precision of the neighboring portion.
Those two methods are selectively used in dependence on an ability of a printing apparatus such as memory storage amount of the printing apparatus or performance of a CPU, the presence or absence of an RIP (Raster Image Processor) server, or a use case.